Induction Motor Quiz

What are the main parts of an induction motor?

• lamination steel, winding

• conductor bar, winding

• Stator, Rotor

What is the formula to calculate the rotating magnetic field speed of an induction motor?

• (number of poles / frequency) * 120

• (120 * frequency) / number of poles

• (frequency * number of poles) / 120

What is one advantage of induction motors?

• Low cost and simple construction

• Limited power output and slow speed

• Low efficiency and high maintenance

input power = 120 W

air gap power = 50 W

converted power = 45 W

mechanical losses = 10 W

find output power

• 55 W

• 35 W

• 105 W

• 15 W

There are 3 ways for starting torque and speed control except

• auto transformer

• primary resistor

• star delta

• capacitor bank

frequency = 50 Hz, motor speed = 980 rpm, pole = 6

determine slip

• 0.02

• 0.04

One of induction motor test is

• block rotor test

• ac resistance test

• short circuit test

change 1500 rpm to rad/s

• 0.25

• 157.08

• 6.37

What is one disadvantage of induction motors?

• Less reliable than other types of motors

• More expensive than other types of motors

• speed not constant

determine SCL

• 50W

• 80W

• 30W